December in Pasadena averages a daily high of 19.7°C with nights around 8.1°C. Expect roughly 6.2 wet days totalling 85.7mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Pasadena is March–June.
Based on PASADENA, CA US (0.1km), 1995–2024. 29 years of December data.